@booklet {barton_novel_2023,
	title = {A novel fluoro-electrochemical technique for classifying diverse marine nanophytoplankton},
	year = {2023},
	month = {apr},
	publisher = {Life Sciences},
	type = {preprint},
	abstract = {<p>To broaden our understanding of pelagic ecosystem responses to environmental change, it is essential that we improve the spatio-temporal resolution of in situ monitoring of phytoplankton communities. A key challenge for existing methods is in classifying and quantifying cells within the nanophytoplankton size range (2-20{\textmu}m). This is particularly difficult when there are similarities in morphology, making visual differentiation difficult for both trained taxonomists and machine learning based approaches. Here we present a rapid fluoro-electrochemical technique for classifying nanophytoplankton, and using a library of 52 diverse strains of nanophytoplankton we assess the accuracy of this technique based on two measurements at the individual level: charge required to reduce per cell chlorophyll a fluorescence by 50\%, and cell radius. We demonstrate a high degree of accuracy overall (\&gt;90\%) in categorising cells belonging to widely recognised key functional groups, however this is reduced when we consider the broader diversity of {\textquotedblleft}nano-phytoflagellates{\textquotedblright}. Notably, we observe that some groups, for example calcifying Isochrysidales, have much greater resilience to electrochemically driven oxidative conditions relative to others of a similar size, making them more easily categorised by the technique. The findings of this study present a promising step forward in advancing our toolkit for monitoring phytoplankton communities. We highlight that, for improved categorisation accuracy, future iterations of the method can be enhanced by measuring additional predictor variables with minimal adjustments to the set-up. In doing so, we foresee this technique being highly applicable, and potentially invaluable, for in situ classification and enumeration of the nanophytoplankton size fraction.</p>
},
	keywords = {RCC1, rcc1084, RCC1130, RCC1150, RCC1178, RCC1185, RCC1198, RCC1216, rcc1217, RCC1242, RCC1314, RCC1346, RCC1489, RCC1511, RCC1546, RCC1557, RCC1614, rcc1731, RCC191, RCC2570, RCC3598, RCC3696, RCC3776, RCC3780, RCC4207, RCC4221, RCC4273, RCC4657, RCC4660, RCC6, RCC623, RCC6516, RCC656, RCC678, RCC69, RCC74, RCC76, RCC8, RCC80, RCC81, RCC88, RCC911, RCC950},
	doi = {10.1002/lom3.10572},
	url = {https://aslopubs.onlinelibrary.wiley.com/doi/10.1002/lom3.10572},
	author = {Barton, Samuel and Yang, Minjun and Chen, Haotian and Batchelor-McAuley, Christopher and Compton, Richard and Bouman, Heather and Rickaby, Rosalind}
}
@article {dore_global_2022,
	title = {Global Phylogeography of Marine Synechococcus in Coastal Areas Reveals Strong Community Shifts},
	journal = {mSystems},
	year = {2022},
	note = {Publisher: American Society for Microbiology},
	pages = {e00656{\textendash}22},
	abstract = {Marine Synechococcus comprise a numerically and ecologically prominent phytoplankton group, playing a major role in both carbon cycling and trophic networks in all oceanic regions except in the polar oceans. Despite their high abundance in coastal areas, our knowledge of Synechococcus communities in these environments is based on only a few local studies. Here, we use the global metagenome data set of the Ocean Sampling Day (June 21st, 2014) to get a snapshot of the taxonomic composition of coastal Synechococcus communities worldwide, by recruitment on a reference database of 141 picocyanobacterial genomes, representative of the whole Prochlorococcus, Synechococcus, and Cyanobium diversity. This allowed us to unravel drastic community shifts over small to medium scale gradients of environmental factors, in particular along European coasts. The combined analysis of the phylogeography of natural populations and the thermophysiological characterization of eight strains, representative of the four major Synechococcus lineages (clades I to IV), also brought novel insights about the differential niche partitioning of clades I and IV, which most often co-dominate the Synechococcus community in cold and temperate coastal areas. Altogether, this study reveals several important characteristics and specificities of the coastal communities of Synechococcus worldwide. IMPORTANCE Synechococcus is the second most abundant phytoplanktonic organism on Earth, and its wide genetic diversity allowed it to colonize all the oceans except for polar waters, with different clades colonizing distinct oceanic niches. In recent years, the use of global metagenomics data sets has greatly improved our knowledge of {\textquotedblleft}who is where{\textquotedblright} by describing the distribution of Synechococcus clades or ecotypes in the open ocean. However, little is known about the global distribution of Synechococcus ecotypes in coastal areas, where Synechococcus is often the dominant phytoplanktonic organism. Here, we leverage the global Ocean Sampling Day metagenomics data set to describe Synechococcus community composition in coastal areas worldwide, revealing striking community shifts, in particular along the coasts of Europe. As temperature appears as an important driver of the community composition, we also characterize the thermal preferenda of 8 Synechococcus strains, bringing new insights into the adaptation to temperature of the dominant Synechococcus clades.},
	keywords = {RCC1086, RCC1695, RCC2369, rcc2380, RCC2553, RCC2556, RCC2570, rcc791},
	doi = {10.1128/msystems.00656-22},
	url = {https://journals.asm.org/doi/full/10.1128/msystems.00656-22},
	author = {Dor{\'e}, Hugo and Leconte, Jade and Guyet, Ulysse and Breton, Sol{\`e}ne and Farrant, Gregory K. and Demory, David and Ratin, Morgane and Hoebeke, Mark and Corre, Erwan and Pitt, Frances D. and Ostrowski, Martin and Scanlan, David J. and Partensky, Fr{\'e}d{\'e}ric and Six, Christophe and Garczarek, Laurence}
}
@article {six_marine_2021,
	title = {Marine Synechococcus  picocyanobacteria: Light utilization across latitudes},
	journal = {Proceedings of the National Academy of Sciences},
	volume = {118},
	number = {38},
	year = {2021},
	note = {Publisher: National Academy of Sciences Section: Biological Sciences},
	abstract = {<p>The most ubiquitous cyanobacteria, Synechococcus, have colonized different marine thermal niches through the evolutionary specialization of lineages adapted to different ranges of temperature seawater. We used the strains of Synechococcus temperature ecotypes to study how light utilization has evolved in the function of temperature. The tropical Synechococcus (clade II) was unable to grow under 16 {\textdegree}C but, at temperatures \&gt;25 {\textdegree}C, induced very high growth rates that relied on a strong synthesis of the components of the photosynthetic machinery, leading to a large increase in photosystem cross-section and electron flux. By contrast, the Synechococcus adapted to subpolar habitats (clade I) grew more slowly but was able to cope with temperatures \&lt;10 {\textdegree}C. We show that growth at such temperatures was accompanied by a large increase of the photoprotection capacities using the orange carotenoid protein (OCP). Metagenomic analyzes revealed that Synechococcus natural communities show the highest prevalence of the ocp genes in low-temperature niches, whereas most tropical clade II Synechococcus have lost the gene. Moreover, bioinformatic analyzes suggested that the OCP variants of the two cold-adapted Synechococcus clades I and IV have undergone evolutionary convergence through the adaptation of the molecular flexibility. Our study points to an important role of temperature in the evolution of the OCP. We, furthermore, discuss the implications of the different metabolic cost of these physiological strategies on the competitiveness of Synechococcus in a warming ocean. This study can help improve the current hypotheses and models aimed at predicting the changes in ocean carbon fluxes in response to global warming.</p>
},
	keywords = {?? Invalid DOI, RCC2035, rcc2382, RCC2385, RCC2421, RCC2527, RCC2535, RCC2553, RCC2570, RCC515, rcc539, rcc752, rcc791, to add},
	issn = {0027-8424, 1091-6490},
	doi = {10.1073/pnas.2111300118},
	url = {http://www.pnas.org/content/118/38/e2111300118},
	author = {Six, Christophe and Ratin, Morgane and Marie, Dominique and Corre, Erwan}
}
@article {Grebert2018,
	title = {Light color acclimation is a key process in the global ocean distribution of Synechococcus cyanobacteria},
	journal = {Proceedings of the National Academy of Sciences},
	volume = {in press},
	year = {2018},
	note = {tex.mendeley-tags: 2018,RCC1016,RCC1017,RCC1018,RCC1020,RCC1023,RCC1027,RCC1030,RCC1031,RCC1084,RCC1085,RCC1086,RCC1087,RCC1096,RCC1097,RCC1649,RCC1661,RCC1688,RCC2032,RCC2033,RCC2035,RCC2319,RCC2366,RCC2368,RCC2369,RCC2370,RCC2372,RCC2373,RCC2374,RCC2375,RCC2376,RCC2378,RCC2379,RCC2380,RCC2381,RCC2382,RCC2383,RCC2384,RCC2385,RCC2415,RCC2432,RCC2433,RCC2434,RCC2435,RCC2436,RCC2437,RCC2438,RCC2457,RCC2525,RCC2526,RCC2527,RCC2528,RCC2529,RCC2530,RCC2532,RCC2533,RCC2534,RCC2536,RCC2553,RCC2554,RCC2555,RCC2556,RCC2567,RCC2568,RCC2569,RCC2570,RCC2571,RCC2673,RCC30,RCC3010,RCC3012,RCC3014,RCC307,RCC316,RCC318,RCC325,RCC326,RCC328,RCC37,RCC44,RCC46,RCC47,RCC515,RCC539,RCC542,RCC543,RCC550,RCC552,RCC553,RCC555,RCC556,RCC557,RCC558,RCC559,RCC62,RCC650,RCC66,RCC752,RCC753,RCC790,RCC791,RCC792,RCC793,RCC794,sbr?hyto?app},
	month = {feb},
	pages = {201717069},
	abstract = {Marine Synechococcus cyanobacteria are major contributors to global oceanic primary production and exhibit a unique diversity of photosynthetic pigments, allowing them to exploit a wide range of light niches. However, the relationship between pigment content and niche partitioning has remained largely undetermined so far due to the lack of a single-genetic marker resolving all pigment types (PT). Here, we developed a novel and robust method based on three distinct marker genes to estimate the relative abundance of all Synechococcus PTs from metagenomes. Analysis of the Tara Oceans dataset allowed us to unveil for the first time the global distribution of Synechococcus PTs and to decipher their realized environmental niches. Green-light specialists (PT 3a) dominated in warm, green equatorial waters, whereas blue-light specialists (PT 3c) were particularly abundant in oligotrophic areas. Type IV chromatic acclimaters (CA4-A/B), which are able to dynamically modify their light absorption properties to maximally absorb green or blue light, were unexpectedly the most abundant PT in our dataset and predominated at depth and high latitudes. We also identified local populations in which CA4 might be inactive due to the lack of specific CA4 genes, notably in warm high nutrient low chlorophyll areas. Major ecotypes within clades I-IV and CRD1 were preferentially associated with a particular PT, while others exhibited a wide range of PTs. Altogether, this study brings unprecedented insights into the ecology of Synechococcus PTs and highlights the complex interactions between vertical phylogeny, pigmentation and environmental parameters that shape Synechococcus populations and evolution.},
	keywords = {2018, RCC1016, RCC1017, RCC1018, RCC1020, RCC1023, RCC1027, RCC1030, RCC1031, rcc1084, RCC1085, RCC1086, RCC1087, RCC1096, RCC1097, RCC1649, RCC1661, RCC1688, RCC2032, RCC2033, RCC2035, RCC2319, RCC2366, RCC2368, RCC2369, RCC2370, RCC2372, RCC2373, RCC2374, RCC2375, RCC2376, RCC2378, RCC2379, rcc2380, RCC2381, rcc2382, RCC2383, RCC2384, RCC2385, RCC2415, RCC2432, RCC2433, RCC2434, RCC2435, RCC2436, RCC2437, RCC2438, RCC2457, RCC2525, RCC2526, RCC2527, RCC2528, RCC2529, RCC2530, RCC2532, RCC2533, RCC2534, RCC2536, RCC2553, RCC2554, RCC2555, RCC2556, RCC2567, RCC2568, RCC2569, RCC2570, RCC2571, RCC2673, rcc30, RCC3010, RCC3012, RCC3014, RCC307, RCC316, RCC318, RCC325, RCC326, RCC328, RCC37, RCC44, RCC46, RCC47, RCC515, rcc539, RCC542, RCC543, RCC550, RCC552, RCC553, rcc555, RCC556, RCC557, RCC558, RCC559, RCC62, RCC650, RCC66, rcc752, RCC753, RCC790, rcc791, RCC792, RCC793, RCC794, sbr?hyto?app},
	issn = {0027-8424},
	doi = {10.1073/pnas.1717069115},
	url = {http://www.pnas.org/lookup/doi/10.1073/pnas.1717069115},
	author = {Gr{\'e}bert, Th{\'e}ophile and Dor{\'e}, Hugo and Partensky, Fr{\'e}d{\'e}ric and Farrant, Gregory K. and Boss, Emmanuel S. and Picheral, Marc and Guidi, Lionel and Pesant, St{\'e}phane and Scanlan, David J. and Wincker, Patrick and Acinas, Silvia G. and Kehoe, David M. and Garczarek, Laurence}
}
